You did nothing wrong. I often read that some people don't get stones the first few times. Just keep doing the flushes, wait another 2 weeks. It sounds at least it worked and the bile came out and with it probably toxins. It was good you had the buttpee so at least cleaning was done and stones might have gotten loosened and might come out the following times.
It is good that you kept drinking water. Just make sure you use Celtic Seasalt to build the minerals up again, if you don't use enough in your food you can spring some in your water.